Description

The process of changing frequency offers many possibilities for communication failure if the pilot subsequently selects the wrong frequency.

Frequency change occurrences are often of short duration because the pilot realises on checking in that he/she is on the wrong frequency: either the frequency is silent, in which case the pilot returns to the previous frequency, or it is active, in which case the controller directs the pilot to the correct frequency.

Frequency change incidents can have serious consequences if the pilot is unable to re-establish contact quickly. This might occur if the previous frequency is very busy, or if the aircraft is out of range of the previous controlling station.